from django.http import HttpResponse, JsonResponse
from django.views.decorators.csrf import csrf_exempt
from rest_framework.parsers import JSONParser
from .models import Snippet
from .serializers import SnippetSerializer


@csrf_exempt
def snippet_list(request):
    """
    List all code snippets, or create a new snippet.
    """
    if request.method == 'GET':
        snippets = Snippet.objects.all()
        serializer = SnippetSerializer(snippets, many=True)
        return JsonResponse(serializer.data, safe=False)

    elif request.method == 'POST':
        data = JSONParser().parse(request)
        serializer = SnippetSerializer(data=data)
        if serializer.is_valid():
            serializer.save()
            return JsonResponse(serializer.data, status=201)
        return JsonResponse(serializer.errors, status=400)


@csrf_exempt
def snippet_detail(request, pk):
    """
    Retrieve, update or delete a code snippet.
    """
    try:
        snippet = Snippet.objects.get(pk=pk)
    except Snippet.DoesNotExist:
        return HttpResponse(status=404)

    if request.method == 'GET':
        serializer = SnippetSerializer(snippet)
        return JsonResponse(serializer.data)

    elif request.method == 'PUT':
        data = JSONParser().parse(request)
        serializer = SnippetSerializer(snippet, data=data)
        if serializer.is_valid():
            serializer.save()
            return JsonResponse(serializer.data)
        return JsonResponse(serializer.errors, status=400)

    elif request.method == 'DELETE':
        snippet.delete()
        return HttpResponse(status=204)


# @csrf_exempt
# def UserRegisterAPIView(request):
#    if request.method == 'POST':
#        data = request.data
#        username = data
#        if User.objects.filter(username__exact=username):
#            return Response("用户名已存在",HTTP_400_BAD_REQUEST)
#        serializer = UserRegisterSerializer(data=data)
#        if serializer.is_valid(raise_exception=True):
#            serializer.save()
#            return Response(serializer.data,status=HTTP_200_OK)
#        return Response(serializer.errors, status=HTTP_400_BAD_REQUEST)
#    elif request.method == 'GET':
#        return Response(status=HTTP_400_BAD_REQUEST)
#
#
# @csrf_exempt
# def UserLoginAPIView(request):
#    if request.method == 'POST':
#        data = request.data
#        username = data.get('username')
#        password = data.get('password')
#        user = User.objects.get(username__exact=username)
#        if user.password == password:
#            serializer = UserSerializer(user)
#            new_data = serializer.data
#            # 记忆已登录用户
#            self.request.session['user_id'] = user.id
#            return Response(new_data, status=HTTP_200_OK)
#        return Response('password error', HTTP_400_BAD_REQUEST)